canonical: https://jentic.com/apis/coincap.io/coincap

# Coincap OpenAPI

CoinCap is a cryptocurrency market data API that aggregates real-time asset prices, exchange listings, market pairs, and conversion rates. Its v3 REST surface is concise - nine endpoints covering assets, asset history, markets per asset, exchanges, and fiat-to-crypto rates. Developers and analysts use it for lightweight crypto pricing without the complexity of full exchange integrations.

## For AI agents

Retrieve live crypto asset prices, historical price series, market pairs, exchange data, and fiat conversion rates from a single REST API.

## Scope

Does not handle wallet management, order placement, or on-chain transactions - use for cryptocurrency pricing and market data only.

## Capabilities

- List ranked crypto assets with current prices, market caps, and supply figures
- Look up a specific asset by slug to retrieve detailed metrics
- Pull historical price series for an asset over a chosen interval
- Browse the markets where a given asset trades and on which exchanges
- List supported exchanges and inspect each one's volume and market count
- Retrieve fiat and crypto conversion rates against a USD reference

## Use cases

### Lightweight Crypto Price Widget

Power a price ticker, dashboard widget, or mobile app card with live crypto pricing without paying for an enterprise data feed. CoinCap returns ranked assets with USD prices, market cap, supply, and 24-hour change in a single call. Integration takes well under an hour.

Example prompt: Call GET /v3/assets with a limit of 10 and return the top assets by rank with their priceUsd values

### Historical Price Charting

Render a price history chart for any supported asset over minute, hour, or day intervals. The /v3/assets/{slug}/history endpoint returns time-series data ready for plotting. Suitable for portfolio apps, blogs, and educational tools.

Example prompt: Fetch hourly history for bitcoin over the past day via GET /v3/assets/bitcoin/history with interval=h1 and return the price points

### Cross-Exchange Market Discovery

Discover where a specific cryptocurrency trades and at what volumes by listing the markets associated with the asset. Useful for arbitrage research, liquidity analysis, and routing trades to the best venue.

Example prompt: Call GET /v3/assets/ethereum/markets and return the top venues by 24-hour USD volume

### AI Crypto Analyst via Jentic

Build an agent that answers ad-hoc crypto questions by combining live and historical CoinCap data through Jentic. The agent expresses an intent in natural language; Jentic routes it to the correct CoinCap endpoint and executes the call with stored credentials. Cost-effective for assistants that need basic crypto pricing without a heavy data subscription.

Example prompt: Through Jentic, fetch the current price and 24-hour change for bitcoin and summarise the move in one sentence

## Key endpoints

| Method | Path | Description |
| --- | --- | --- |
| GET | /v3/assets | List ranked crypto assets with current market data |
| GET | /v3/assets/{slug} | Look up a specific asset by slug |
| GET | /v3/assets/{slug}/history | Retrieve historical price series for an asset |
| GET | /v3/assets/{slug}/markets | List markets where a given asset trades |
| GET | /v3/exchanges | List supported cryptocurrency exchanges |
| GET | /v3/rates | List conversion rates |

## Key resources

- **Assets** — List, look up, and pull history for cryptocurrency assets
- **Markets** — Browse trading pairs and per-asset market venues
- **Exchanges** — List supported exchanges and inspect per-exchange metadata
- **Rates** — Get conversion rates between supported currencies

## Why Jentic

- **Setup:** Wiring CoinCap by hand means setting up its bearer token auth against the rest.coincap.io host and handling pagination and rate limits across its asset and market endpoints yourself. Through Jentic you install once, import CoinCap from the API Directory, store the token once, and your agent calls it.
- **Permission scoping:** CoinCap serves read-only pricing and market data, so you scope by choosing the operations the agent may call: limit it to what it needs, such as reading an asset price or listing exchanges, and broader calls like full history retrieval are not included unless you add them.
- **Credential handling:** Your CoinCap bearer token is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context.
- **Discovery method:** Agents search Jentic by intent such as 'get the current bitcoin price' or 'list markets for an asset', and Jentic returns the matching CoinCap operation with its input schema so the agent calls the right endpoint without browsing the reference docs.

## Related APIs

- **CoinGecko API** — Broader free crypto data with deeper coverage of altcoins and DeFi tokens
- **CoinMarketCap API** — Industry-standard rankings, listings, and market cap data
- **CoinAPI Market Data REST API** — Exchange-level granularity with OHLCV, trades, and order books

## FAQ

### What authentication does the CoinCap API use?

CoinCap v3 uses bearer token authentication - pass your API key in the Authorization header as Bearer {key}. Through Jentic, the key is stored in the encrypted vault and the agent receives a scoped execution token rather than the raw bearer string.

### Can I retrieve historical price data with the CoinCap API?

Yes. GET /v3/assets/{slug}/history returns price points for a chosen asset over an interval such as m1, m5, h1, h2, h6, h12, or d1. Pair the interval with start and end timestamps to bound the range.

### What are the rate limits for the CoinCap API?

Rate limits depend on the API key tier. The OpenAPI spec does not declare per-endpoint thresholds; check the tier attached to your CoinCap account. Free keys have lower throughput than paid tiers.

### How do I look up a single asset price through Jentic?

Install the SDK with pip install jentic, search Jentic for get current crypto asset price, load the schema for GET /v3/assets/{slug}, and execute with the asset slug (for example bitcoin).

### Does CoinCap return data for stablecoins and fiat currencies?

Stablecoins are listed in /v3/assets like any other crypto asset. Fiat conversion rates are exposed separately via /v3/rates and /v3/rates/{slug}, both quoted relative to USD.

### Can I see which exchanges trade a specific cryptocurrency?

Yes. GET /v3/assets/{slug}/markets returns the trading pairs and exchanges where the asset is listed, along with per-market 24-hour USD volume - useful for liquidity and arbitrage analysis.

### Can I limit what my agent is allowed to do with the CoinCap API?

Yes. Because Jentic One is self-hosted, you decide which CoinCap operations your agent may call and which credentials it uses. CoinCap is read-only pricing and market data, so you can grant only the calls the agent needs, such as reading an asset price with GET /v3/assets/{slug} or listing exchanges with GET /v3/exchanges, while withholding broader operations like full history retrieval via GET /v3/assets/{slug}/history unless you add them. Your rules set the boundary, and the stored bearer token is injected only for the operations you permit.